Field of the Invention
The invention relates to a technology for detecting an object in a vicinity of a vehicle.
Description of the Background Art
Conventionally, an object detection apparatus has been proposed that detects an object by using captured images captured by a camera for capturing images of a vicinity of a vehicle. The object detection apparatus detects an object based on captured images captured by, for example, a front camera. Since a user (mainly a driver) is informed of a detection result detected by such an object detection apparatus, the user can easily understand an object, for example, a vehicle approaching from a blind area in a traffic intersection or in a parking lot with poor visibility.
Optical flow method is well known as a detection method used for such an object detection apparatus to detect an object. The optical flow method extracts feature points from the captured images (frame) periodically obtained to derive optical flows that serve as vectors indicative of movement of feature points between the captured images. Based on the optical flows, the object detection apparatus detects an object in a vicinity of a host vehicle.
In a case where the optical flow method is used, while the host vehicle is travelling, in addition to the optical flows of a moving object, optical flows of a background are derived. Such an optical flow of the background causes a false detection of an object.
A detection sensitivity of the conventional object detection apparatus is fixed at a predetermined level to avoid such false detection of an object. Therefore, it is difficult to improve object detection performance of the object detection apparatus.